Mixing vial

ABSTRACT

A mixing vial having a hollow interior chamber with a tubular portion having distal and proximal open ends and a stopper positioned in sealing relationship in the tubular portion, the stopper having a hollow interior chamber with an open end and a dislodgeable plug positioned in and sealing the open end.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of provisional patent applicationSer. No. 62/441,431, filed Jan. 1, 2017 by John Scott Keadle, which isincorporated by reference in its entirety.

FIELD OF THE INVENTION

This application relates to chemical vials. More particularly thisapplication relates to medical and dental vials for storage, mixing anddelivery of drugs such as buffered anesthetic solutions.

BACKGROUND OF THE INVENTION

For various reasons, some drugs must be stored and transported in twoparts, and then mixed together just prior to administration. Forexample, steroid drugs in powder form are sometimes mixed with variousvehicles just prior to injection and local anesthetics are sometimesmixed with NaHCO3 buffering solution just prior to injection.

In addition, some drugs require agitation immediately prior toinjection, and therefore require headspace for effective agitation,while at the same time being susceptible to oxidative degradation whichoccurs during storage from the gas in the headspace. These drugs benefitfrom vials that eliminate headspace during storage, but allow headspacefor agitation just prior to injection.

Local anesthetic solution exerts its effect by blocking transmission ofthe nerve signal in the area of the nerve where the solution has beendeposited. Generally speaking anesthetic solutions must be acidified toan acid pH of about 4.0 (akin to vinegar) to obtain adequate shelf life.This acid solution is painful to the patient when injected, and is justone more reason that people don't like getting shots at the dentists' orphysicians' office. In addition, the drug does not exert any effect atthis low “storage” pH, so the patient must wait several minutes afterinjection before the numbness begins, while their body slowly brings thepH up to that of the body tissues, which is about 7.4.

Overwhelming evidence demonstrates that raising the pH of the anestheticto a pH closer to neutral just prior to injection (“buffering”) greatlydecreases the pain associated with injection, as well as the latency ofthe anesthetic effect. Because of this, many inventors over severaldecades have attempted to help make buffering a widespread practice inboth dentistry and medicine, but at present no method has beensatisfactory for a number of reasons.

Sodium bicarbonate (NaHCO3) in an 8.4% aqueous solution is the mostcommon solution used to buffer anesthetic. The NaHCO3 solution and thelocal anesthetic solution are typically mixed in a ratio of about 9parts anesthetic to 1 part NaHCO3 solution.

When physicians, such as dermatologists and plastic surgeons, buffertheir anesthetic, they first draw anesthetic solution into their syringefrom a vial, and then add NaHCO3 solution to the syringe by drawing itfrom a separate vial. The unused anesthetic and NaHCO3 solutions, intheir respective vials, along with the needle and syringe, must bediscarded after each patient. This protocol typically wastes more than90% of the NaHCO3, and two vials are required. In addition, the mixingprotocol is subject to human error and has resulted in protocolbreaches, including improper drug ratios, sterility breaches, andintentional “re-use” of single-patient drug vials on other patients,with resulting adverse medical outcomes. This method is also somewhatcumbersome, time-consuming, and uneconomical. However, despite the riskand the cost in time and money, many physicians buffer their anesthetic,as it makes a significant difference in the patient's comfort whenperformed properly.

It would be preferable to have a system for the physician to draw andmix anesthetic medications using only one vial. Drawing from one vialinstead of two would save valuable time, make the process safer, savethe costs of the extra vial and the excess buffer solution, result inmore widespread use of buffering, and increase patient comfort.

In the oral environment, because of the special need for dexterity andthe likelihood of multiple injections on the same patient, dentiststypically inject the anesthetic solution with a reusable hand-held metalsyringe, which has evolved and consolidated into a single design thataccounts for almost all syringes in use in dentistry and oral surgery.This syringe is used in conjunction with a disposable hollow injectionneedle which is attached to the syringe and a specialized glass drugvial called a “cartridge” or “carpule” of anesthetic solution, which isplaced into the syringe. As the cartridge is placed into the syringe,the cartridge is pierced by the back end of the needle, so that solutioncan flow out and through the needle. The cartridge has a piston that isdriven by a pushrod on the syringe, so that when the dentist pushes onthe pushrod the piston drives the solution through the attached needle.

The cartridge has the shape of an elongated barrel. The cartridge issealed on one end with a puck shaped elastomeric membrane that isfastened with a crimped metal cap in the manner typical of most glassdrug vials A notable and important difference between a dental cartridgeand a typical drug vial is the size. A dental cartridge volume istypically less than 2 ml, due mainly to limitations imposed by thesyringe fitting in the operator's hand and its use in the mouth, whereasa typical drug vial has a volume of 10-100 ml.

Dentists who buffer their anesthetic typically use one of twocommercially available systems. Both of these systems add considerabletime and expense to the procedure. The ongoing product cost perinjection of the commercially available systems is many times that of anunbuffered protocol. One system for dentists requires dentists to use asyringe/needle combination that is very different than the standardsystem that is ubiquitous in the industry. This system also requires acountertop device that contains both anesthetic solution and NaHCO3solution in separate vials and is used to load the disposablesyringe/needle combination. This is time consuming, expensive, and itsuse is subject to operator error and breaches of sterile andpharmacological protocol.

Another system for dentists utilizes an injector that introduces NaHCO3into the standard dental cartridge. This system requires that eachcartridge be separately loaded with NaHCO3, which is time consuming, andin some states legally prohibited except by licensed pharmacists. Inaddition, this system causes a significant loss of available drug volumein the cartridge as well as being subject to operator error and breachesof sterile and pharmacological protocol.

In spite of their disadvantages, both systems have found a limitedmarket, demonstrating that buffering is very desirable from both adentist's and a dental patient's perspective. Making the bufferingprocess less time consuming, less expensive, safer, and more similar tocurrent surgical protocol would result in more widespread use for thebenefit of both patient and dentist.

In the case of steroid drugs, physicians typically are provided with aspecial glass vial that has been partitioned into two chambers. Theglass vial is provided with a plunger mechanism that the physicianmanually depresses to mix the contents of the chambers. The “Act-O-Vial”is typical of these special vials. The Act-O-Vial consists of sevenparts and requires a specially shaped glass vial and apparatus.

The Act-O-Vial and similar special vials are also used in conjunctionwith drugs which require headspace for agitation, but benefit from alack of headspace during storage. In this case, the fluid in the firstchamber is stored without headspace, and then utilizes the headspace inthe second chamber to permit agitation.

There remains a need to provide a less time consuming and less expensivemethod for in situ mixing or agitation of drugs, notably including thebuffering of local anesthetic and the mixing of steroids for injection.Accordingly it is desired to provide various embodiments of the presentinvention as follows: to provide a mixing cartridge suited for use withdental syringes which may be manufactured more simply, using an extrudedhollow glass tube that is cut to length, rather than a complicated formrequiring each cartridge to be individually blown around a mandrel; tosimplify the filling and sealing of the dental cartridge by requiringfewer and simpler parts; to eliminate the use of metal crimped caps forsealing, along with the metal dirt and dust which contaminates the cleanor sterile assembly lines required for the manufacture of dentalcartridges; to provide maximal interior volume to contain a drug; tofacilitate the ability to eliminate gaseous headspace and the associatedoxidative degradation of the drug in a dental cartridge; to provide amixing dental cartridge that allows maximum interior volume for drugstorage while minimizing breakage; to provide mixing or agitation ofdrugs used in medicine or dentistry using a minimum of simple parts; toreduce the possibility of operator error and breaches in sterile orpharmacological protocol when mixing drugs; to provide a mixing vialstopper which may be used with the typical medical vial and the typicalcrimped sealing cap, rather than requiring a specially shaped vial thatis difficult to manufacture or a multipart sealing mechanism; to savetime and cost, to facilitate accurate proportioning of materials to bemixed and avoid operator error; to make widespread the use of localanesthetic buffering; to reduce pain and waiting time in theadministration of local anesthesia in medical and dental offices.

Other advantages of one or more aspects will be apparent from thefollowing disclosure and claims taken in conjunction with theaccompanying drawings.

SUMMARY OF THE INVENTION

A mixing vial has a unitary hollow chambered vial stopper with adislodgeable plug separating the hollow stopper chamber from the vialchamber. The plug may be dislodged to allow mixing of the contents ofthe stopper chamber and the vial chamber or agitation of a drug in theheadspace created.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side elevation of a conventional needle/syringe apparatusfor use in combination with a vial of the present invention;

FIG. 2 is a perspective view of a conventional vial having a singlechamber;

FIG. 3 is an exploded, sectional view, in vertical section, of anembodiment of a mixing vial of the present invention with itsdislodgeable plug in sealing position and a needle, broken away;

FIG. 4 is a sectional view, in vertical section, of an embodiment ofFIG. 3 with its plug dislodged and a needle, shown broken away, theneedle having been inserted into the vial to dislodge the plug;

FIG. 5 is a side elevation of a conventional dental cartridgeneedle/syringe apparatus for use in combination with a cartridge of thepresent invention;

FIG. 6 is an exploded sectional view, broken away, of the conventionaldental cartridge needle/syringe apparatus of FIG. 5;

FIG. 7 is a perspective view of a conventional dental cartridge having asingle chamber;

FIG. 8 is a sectional view of an embodiment of a mixing vial of thepresent invention in cartridge form with a needle inserted therein, theneedle shown broken away;

FIG. 9 is a sectional view of the embodiment of FIG. 8, with a needleinserted therein, the needle shown broken away, after theharpoon-plunger of the syringe has been inserted into and through thehollow chambered piston and dislodged the plug; and

FIG. 10 is a sectional view, broken away, of an embodiment of a mixingvial of the present invention in cartridge form with a needle insertedtherein, the needle having dislodged the plug to effect mixing of thetwo chambers' contents.

DESCRIPTION OF THE INVENTION

Now referring to the drawings, a conventional prior art syringe/needleapparatus is illustrated in FIG. 1 while a conventional prior art vialis illustrated in FIG. 2. The syringe/needle apparatus of FIG. 1 issuitable for use in conjunction with an embodiment of the mixing vial ofthe present invention as will be described in more detail in thefollowing disclosure. The conventional prior art vial does not have dualchambers or a plug and is shown for illustrative purposes.

FIGS. 3 and 4 illustrate a mixing vial of the present invention which isindicated by the numeral 10. Mixing vial 10 provides the ability forphysicians to buffer local anesthetic prior to injection in a mannerthat is economically feasible, is not excessively time-consuming, doesnot interfere with established surgical protocol, and does not requirenew or unfamiliar surgical equipment.

Broadly speaking, mixing vial 10 is a generally barrel shaped vessel 12having a hollow interior chamber 14 and neck 16 having distal andproximal open ends, 18 and 20. An elastomeric, chambered stopper 22 ispositioned in neck 16 and is in sealing relationship with interiorfacing wall 24 of neck 16.

Chambered stopper 22 has a hollow interior chamber 26 and an openproximal end 28 with a dislodgeable plug 30 positioned in and sealingsaid open end 28. Thus, annular edge 32 of plug 30 is tightly fit intoannular groove 34 in radially inwardly extending stopper flange 36 ofstopper 22. Vessel 12 may be made of glass, plastic or any othermaterial suitable for use consistent with the purpose of the presentinvention. Stopper 22 may be made of elastomeric plastic or rubbermaterial, including the typical vial stopper material in present use,which will seal well with adjacent surfaces. Plug 30 may be made ofPTFE, or any material or combination of materials suitable for sealingwith stopper 22 and resisting penetration of the needle. For instance,plug 30 may have an elastomeric body and edge, with a PTFE strike plate31 attached to the needle side to prevent needle penetration.

Stopper 22 has a radially outwardly extending annular flange 38 and isretained in position on neck 16 by metal clip 40 which clips ontoannular shoulder 42 on neck 16 and compresses flange 38 against distalface 45 of neck 16.

As shown in FIGS. 3 and 4, interior chamber 14 of vessel 12 containssolution 50, for example, a local anesthetic solution, or a physiologicsaline solution. Interior chamber 26 of stopper 22 contains a powder 52,for example, NaHCO3, or a powdered steroid medication.

In operation, the mixing vial 10 of the present invention is used inaccordance with the following method. First, a mixing vial of thepresent invention is provided and its two chambers filled with suitabledrugs or other materials which are desired to be kept separate and thenmixed just before injection. Then, the vial is inverted and, using atypical disposable medical syringe 53 as illustrated in FIG. 1, thephysician inserts the Syringe Needle 55 into the chambered stopper 22 asillustrated in FIGS. 3 and 4. The physician must make certain that theSyringe Needle passes through chamber 26 of stopper 22 and dislodgesplug 30 into the chamber 14 of mixing vial 10. The dislodged plug 30 mayfloat to the top of the mixed solution, or alternatively be configuredto stay in solution to aid in mixing the drugs. Also, vial 10 may beshaken to assist in mixing. Coloring or clouding reagents may be addedto either chamber to provide visual indication of mixing or prematureseal failure. The form of the Chambered Vial Stopper assembly allowselimination of headspace gas in one or the other of the chambers. Thephysician withdraws the mixed drug solution from the inverted vial intothe syringe apparatus and administers it to the patient in the typicalmanner.

Now referring to FIGS. 5 and 6 a conventional syringe 57 for use withvials configured as cartridges such as the conventional dental cartridge59 shown in FIG. 7 is illustrated. The conventional cartridge syringe isalso useful for use with a cartridge style mixing vial of the presentinvention as further described below.

As shown in FIGS. 8 and 9, mixing vial 110 is in the form of a cartridgeand has a generally barrel shaped vessel 112 having a hollow interiorchamber 114 and neck 116, and having distal and proximal open ends, 118and 120. Neck 116 is a portion of vessel 112 at the proximal end thereofand is simply an extension of the vessels tubular structure, the wallthickness, and diameter of vessel 112 not being reduced for neck 116. Anelastomeric, chambered stopper-piston 122 is positioned in neck 116 andis in sealing relationship with interior facing wall 124 of neck 116.

Chambered stopper-piston 122 has a hollow interior chamber 126 and anopen distal end 128 with a dislodgeable plug 130 positioned in andsealing said open end 128. Thus, annular edge 132 of plug 30 is tightlyfit into annular groove 134 in radially inwardly extending stopperflange 136 of stopper 122. Vessel 112 may be made of glass, plastic orany other material suitable for use consistent with the purpose of thepresent invention. Stopper-piston 122 may be made of elastomeric plasticor rubber material which will seal well with adjacent surfaces. Plug 130may be made of PTFE, or any material or combination of materialssuitable for sealing with stopper-piston 122 and resisting penetrationof the harpoon-plunger 146. For instance, plug 130 may have anelastomeric body and edge, with a PTFE strike plate 131 attached to theharpoon side to prevent harpoon penetration. Plug 130 may take the formof a sphere, convex disc, or other forms, and may be used for agitationof the chemicals to be mixed. Stopper-piston 122 may have annular ribs138 or other aids for sealing and stability.

Open distal end 118 of vessel 112 is sealed by rubber sealing cap 133which is held in place by metal clip 140.

In use, it is intended that cap 133 will be pierced by needle 142, asillustrated in FIG. 9, when medical mixing vial, or cartridge, 110 isplaced in syringe 57. Then, pushrod 146 is moved downwardly to firstpierce stopper 122 and then dislodge plug 130 as illustrated in FIG. 9.Chemical reagent 148 such as buffering material in chamber 126 ofstopper 122 is thus allowed to mix with solution 150 in chamber 114. Themixture of drugs is then injected into a patient by manipulating pushrod146 further downwardly, with shoulder 152 of pushrod 146 pushing againststopper 122 to push stopper 122 downwardly to act as a piston, slidingdown vessel 112 and hydraulically expelling the liquid therein throughneedle 142.

Another embodiment is shown in FIG. 10. As shown in FIG. 10, mixing vial210 is in the general form of a syringe cartridge and has a generallybarrel shaped vessel 212 having a hollow interior chamber 214 and neck216 having distal and proximal open ends, 218 and 220. Neck 216 is aportion of vessel 212 at the distal end thereof and is simply anextension of the vessels tubular structure, as the wall thickness anddiameter of vessel 212 are not changed for neck 216. An elastomeric,chambered stopper 222 is positioned in neck 216 and is in sealingrelationship with interior facing wall 224 of neck 216. Stopper 222 hasa radially outwardly extending annular flange 238 and ribs 239 and 241and is retained in position in neck 216 during storage and transport byfriction with vessel 212. During use, retention of stopper 222 in neck216 is insured by proximally facing face 260 of syringe 57.

Chambered stopper 222 has a hollow interior chamber 226 and an openproximal end 228 with a dislodgeable plug 230 positioned in and sealingsaid open end 228. Thus, annular edge 232 of plug 230 is tightly fitinto annular groove 234 in radially inwardly extending stopper flange236 of stopper 222. The proximal face of stopper flange 236 may haveradial grooves 237 to provide flow should plug 230 become lodged againstproximal face of flange 236 after dislodgement from groove 234.

Vessel 212 may be made of glass, plastic or any other material suitablefor use consistent with the purpose of the present invention. Stopper222 may be made of an elastomeric plastic or rubber material, includingthe typical vial stopper material in present use, which will seal wellwith adjacent surfaces. Plug 230 may be made of PTFE, or any material orcombination of materials suitable for sealing with stopper 222 andresisting penetration of the needle. For instance, plug 230 may have anelastomeric body and edge, with a PTFE strike plate 233 attached to theneedle side to prevent needle penetration. Stopper 222 may have annularribs or other sealing and retentive aids. Neck 216 may have inwardlyfacing grooves, ledges, or flanges to aid in sealing and retention ofstopper 222.

Open proximal end 220 of vessel 212 is sealed by piston 252. Piston 252is shown with a hollow recess 254 in the distal face which addsavailable volume inside the interior chamber 214 of the mixing vial 210and prevents damage to the proximal end of needle 142 as piston 252translates distally.

In use, it is intended that stopper 222 will be pierced by needle 142,as illustrated in FIG. 10 when mixing vial, or cartridge, 210 is placedin syringe 144. Then, needle 142 dislodges plug 230 from stopper 222, asproximally facing syringe face 260 abuts stopper distal face 240 andprevents hydraulic dislodgement. Chemical reagent 248 such as bufferingmaterial in chamber 226 of stopper 222 is thus allowed to mix withsolution 250 such as local anesthetic in chamber 214. The mixture isthen injected into a patient by manipulating syringe pushrod 146distally against piston 252, hydraulically expelling the liquid throughneedle 142.

While embodiments of the present invention have been disclosed, it willbe appreciated by those skilled in the art that the invention is subjectto variations and modifications and it is intended that the inventionwill be limited only by the following claims. For example, asalternatives to the embodiments disclosed, the vial may be of three ormore chambers instead of two, allowing the mixing of more components.The vial may serve to enhance the in-situ mixing of chemicals inapplications not specifically mentioned here or in applications not yetcontemplated. The materials to be mixed in either chamber may be asolid, powdered solid, fluid, gas, or a mixture of any or all of theabove. Coloring, clouding, or other reagents may be used to visuallyindicate mixing of the components or leakage of the seals between thechambers or the exterior. The plug to be dislodged may be rigid, ormainly rigid with an elastic portion or mainly elastic with a rigidportion. The stopper may be elastic, or mainly elastic with a rigidportion, or mainly rigid with an elastic portion. Any of the parts mayinclude features that improve, simplify, or shorten the manufacturing ofthose parts or improve, simplify, or shorten the assembling of theoverall apparatus. Any of the parts or the overall apparatus may includefeatures that improve the visual marketing appeal of the apparatus. Thevessel or any part of the vessel, while described in the embodiments ashaving a generally circular cross-section in one plane, may have anyother shape in cross-section that permits use.

What is claimed is:
 1. A syringe system, the system comprising: a syringe with an axially movable plunger having a distal end defining a shoulder, wherein a harpoon extends axially from the distal end of the plunger, wherein the shoulder has a larger diameter than a harpoon minimum diameter, wherein the harpoon is static with respect to the plunger; and a mixing vial for use in the syringe, said mixing vial including: a vessel, the vessel comprising a hollow interior chamber with proximal and distal ends, a neck at the proximal end, the neck having distal and proximal open ends; and a stopper-pistol the stopper-piston comprising a hollow interior chamber with an open distal end and a closed proximal end, and the entire shipper-piston being slidably positioned in a sealing relationship with said neck, wherein the entire stopper-piston is slidable from a first position to a second position, wherein the entire stopper-piston is adjacent the proximal end of the vessel when in the first position, and wherein the entire stopper-piston is closer to the distal end of the vessel than to the proximal end of the vessel when in the second position; and a dislodgeable plug positioned in and sealing said open distal end of said hollow interior chamber of the stopper-piston, wherein the entire dislodgeable plug is fully dislodgeable as a single piece from the open distal end of the stopper-piston; wherein said stopper-piston comprises a radially inwardly extending flange, wherein the radially inwardly extending flange defines an inward facing annular groove that receives an edge of the dislodgeable plug, wherein a stopper-piston breakout force is required to cause the stopper-piston to slide in a direction from the first position toward the second position, and a plug dislodging force is required to fully dislodge the dislodgeable plug from the inward facing annular groove defined by the radially inwardly extending flange of the stopper-piston in the direction from the first position toward the second position, wherein the plug dislodging force is less than the stopper-piston breakout force; and wherein, when the mixing vial is disposed in the syringe and the plunger is axially moved, the harpoon penetrates the closed proximal end of the stopper-piston, contacts the dislodgeable plug, and fully dislodges the dislodgeable plug prior to the shoulder of the plunger contacting the closed proximal end of the stopper-piston.
 2. The system of claim 1, wherein said interior chamber of said vessel comprises an anesthetic, and said interior chamber of said stopper-piston comprises a buffering reagent.
 3. The system of claim 1, wherein the syringe comprises a dental syringe, the vessel comprising a shape that allows use with the dental syringe.
 4. The system of claim 1, wherein the distal end of the vessel is open and sealed by a sealing cap.
 5. The system of claim 1, wherein the stopper-piston comprises an elastomeric plastic or rubber.
 6. The system of claim 4, wherein the stopper-piston slides within the hollow interior chamber of the vessel.
 7. The system of claim 4, wherein the harpoon pierces the stopper-piston and dislodges the dislodgeable plug when the mixing vial is loaded into or placed in the syringe.
 8. The system of claim 7, wherein said interior chamber of said vessel comprises an anesthetic, and said interior chamber of said stopper-piston comprises a buffering reagent, and the anesthetic and the buffering reagent are mixed.
 9. The system of claim 1, wherein the plug dislodging force is less than the a force necessary to penetrate the dislodgeable plug.
 10. The system of claim 1, wherein the dislodgeable plug includes a strike plate, wherein the dislodgeable plug is disposed within the open distal end of the stopper-piston such that the strike plate faces the hollow interior chamber of the stopper-piston, the strike plate being configured to resist penetration by the harpoon when the harpoon is used to dislodge the dislodgeable plug. 